ACWR in 30 Seconds: Load Spike Check for Track Coaches
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You coach 22 athletes across sprints, hurdles, jumps and 800 m. Between the day job, two evening sessions and the weekend meet, you have about 30 seconds per athlete on Sunday evening to decide whether Tuesday's plan still stands. ACWR, the acute:chronic workload ratio, is built for exactly that half minute.
This is the short version. If you want the full explanation with the formula and a worked example, read ACWR explained for track and field coaches. Here you get the routine: what the number means, where to look, and what to change.
ACWR in one sentence
ACWR compares the training load of the last 7 days with the athlete's average week over the last 28 days. A 1.0 means this week matched the athlete's recent normal. A 1.5 means this week was half as big again as the base behind it. That is a load spike, and load spikes are where hamstring strains and shin pain tend to start.
The load behind the number is usually session RPE times minutes, one number per session that covers a block-start session, a throws session and a 1500 m tempo run alike.
The Sunday routine
Open the group view. Sort by ACWR. Three questions, in order.
1. Who is above 1.3? These are the athletes whose week stepped up noticeably. For each one, open the sessions behind the number. A camp week or the first week of a new block explains most of them. Then check sleep, soreness and pain from the daily check-ins. Stable check-ins and a planned step-up: hold the plan. Drifting check-ins or a new pain entry: trim Tuesday.
2. Who is above 1.5? This is the group that needs a real look, not a glance. Find out which sessions produced the spike. Often it is a test meet with three rounds, or a thrower who started a heavy strength block in the same week as a throws camp. Reduce the volume of the next two or three sessions and keep the intensity. Ask the athlete one direct question at Tuesday's warm-up.
3. Who is below 0.8? A sudden drop means illness, exams, a holiday, or an athlete who stopped logging. Planned taper weeks belong here too and need nothing. For everyone else, the return next week should be gradual rather than a "catch-up" week, which would create next Sunday's spike.
Everyone between 0.8 and 1.3 gets no extra attention. That is what makes the routine fit into a Sunday evening with 22 athletes.
Decision rules you can apply at the track
| Situation | What you see | Tuesday's change |
|---|---|---|
| Planned step-up | ACWR 1.3 to 1.5, check-ins stable | None. Do not add a second step-up next week. |
| Step-up plus drift | ACWR 1.3 to 1.5, sleep or soreness worse for 2 or more days | Keep the session intent, cut reps by a quarter to a third. |
| Spike | ACWR above 1.5 | Replace one speed or jumps session with technique and short accelerations. Reassess Thursday. |
| Spike plus pain | ACWR above 1.5 and a new pain entry | No full-speed running or full jumps until the pain entry has cleared for two consecutive days. |
| Drop | ACWR below 0.8, not a taper | Return with a normal week, not a bigger one. |
What a spike looks like by event group
Sprints and hurdles spike on intensity, not duration. The first week of full-speed block starts after an acceleration phase can push the ratio past 1.4 while the total distance stays tiny, because the athletes rate those sessions 8 or 9. Jumpers spike on full-approach jumps; counting them separately helps. Throwers spike in the weight room: a new strength block plus 40 throws per session is the classic case. Middle-distance runners spike in camp weeks and when a road race lands on top of a normal week.
Three mistakes that waste the 30 seconds
Reading one day. The ratio moves every day. Look at the direction over the week, not at the value after a long Saturday.
Comparing athletes to one threshold. The ratio is relative to each athlete's own base. A 1.4 for a senior thrower with a big base and a 1.4 for a 15-year-old hurdler returning from illness are different situations.
Trusting the number when the logs are incomplete. Three missing sessions in the chronic window inflate this week's ratio. If an athlete has gaps, fix the logging before you change the plan.
How Athlog helps
Athlog was built for track and field groups, and the Sunday routine above is the group view. ACWR is calculated automatically from the RPE and minutes your athletes enter after every session, and it sits next to their sleep, soreness, mood and pain entries.
- Group view sorted by ACWR, so the three or four athletes who need a look are at the top
- Session history behind every number
- Daily check-ins next to the ratio, so a planned step-up and a problem look different
- A direct message to the athlete from the same screen
See the coach view on the track and field page.
FAQ
Is 1.5 a hard limit?
No. It is the point at which you should open the sessions and the check-ins and decide deliberately. Athletes with a large, consistent base tolerate a 1.5 better than athletes with a small or interrupted one (Gabbett, 2016).
How long until the number means anything?
Four weeks of consistent logging. Before that, the chronic load is noise. Collect data, run the routine anyway to build the habit, and start acting on it from week five.
Do I need wearables?
No. Session RPE times minutes is enough, and it is the only method that covers every session type in a mixed training group with one number. See tracking training load without wearables.
This week
- Make sure every athlete has four weeks of sessions logged with RPE and minutes.
- On Sunday, sort the group by ACWR and look only at athletes above 1.3 or below 0.8.
- For each of them, open the sessions and the check-ins, then decide Tuesday's change using the table above.
- Ask one question at Tuesday's warm-up and write the answer in the athlete's notes.
- Repeat next Sunday. The routine gets faster every week.
Related: 3 signs an athlete needs a deload.
This guide shares coaching knowledge, not medical advice: for persistent pain, illness or unexplained fatigue, consult a healthcare professional.